16 1 Vol 16 No 1 2010 2 ELECTROCHEMISTRY Feb 2010 1006-3471 2010 01-0060-05 * 361005 O646 A 1 2 ph > 12 5 2-3 5-7 ph Fe Fe 2 + + 2e Cl - 4 O 2 + 2H 2 O + 4e 4OH - Cl - CO 2 / 8 Cl - CO 2 H 2 O O 2 9-10 11-13 14-15 1 2009-04-26 2009-05-03 * Tel 86-592 2189354 E-mail cjlin@ xmu eud cn 50731004 2007BAB27B04
1 61 1 1 1 10 0 3 mm 10 μm 10 10 1 Fig 1 Schematic diagram showing the array electrode for 1 2 simulating measurement corrosion behavior of reinforcing steel in concrete 0 9mm 1 3 0 6 57 mm 60 mm 10 mm 24 h 28 d 1 3 1 3 5% NaCl / 2 3 5% NaCl Fig 2 Variations of corrosion potential of array electrode GS510 with the electrode position in concrete immerging in 3 5% NaCl solution Autolab Potentiostat Galvanostat Autolab 10 d 4# - 500 mv ± 15 mv vs OCP 1 mv /s 2 4# 25 d 2 1 10# 2 3 5% NaCl / 1 d - 200 mv 10# 1# 10# 7d 2 2 4# - 450 3 mv
62 2010 7 d 4# 21 d 1# 2# 3# 4# 30 d 1# ~ 4# 4# / 4 Fig 4 Variations of microcell current density of array electrode with the electrode position in concrete immerging in 3 5% NaCl solution 3 Fig 3 Variations of macrocell current density of array electrode with the electrode position in concrete immerging in 3 5% NaCl solution 2 3 2 ~ 3 7 d 4# 1# 2# 3# 10# 30 d 5# ~ 9# 1# ~ 4# 5 ~ 9# 4 Autolab 7 d 10 d 4# 30 d 1# ~ 5# 6# 7# 9# 7 d 4# 8# 10# 4 0 / 2 4
1 63 1# 14 d 21 d 5# 6 # 7# 9# 2 3 4 5 10 d 4# 21 d 4# 1# 2# 3# 30 d 1# ~ 4# 10# / ph Cl - / 5 3 5% NaCl Fig 5 Distributions of macrocell corrosion current microcell corrosion current and corrosion potential of ar- ray electrode in concrete immersed in 3 5% NaCl / at different time a 10 d b 21 d c 30 d / 3 3 1 2 / References 1 Hong D H Corrosion and protection of rein-
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